1. Description of the Ideal Vapour Compression Cycle on the P-H Diagram

The Pressure-Enthalpy (P-H) diagram is the most practical representation for the VCS, as the system's performance metrics (work and heat) are directly proportional to changes in enthalpy (h).

The diagram features a saturation dome, with the saturated liquid line on the left and the saturated vapor line on the right. The cycle is composed of four distinct points connected by four processes: